BIO MODULE 5:Set 2 — Chromosomes & Interphase

What is chromatin?

The loose, relaxed form of DNA found in the nucleus of eukaryotic cells.

What are chromosomes?

Condensed packages of DNA containing genetic information that is distributed during cell division.

What is a chromatid?

One half of a duplicated chromosome.

What are sister chromatids?

Two copies of a replicated chromosome joined together before separation.

What is chromosome segregation?

The equal distribution of daughter chromosomes between the two cells produced by division.

What is ploidy?

The number of chromosome sets in a cell or species.

What does diploid (2n) mean?

A cell has two sets of chromosomes.

What does haploid (n) mean?

A cell has one set of chromosomes.

What are the four phases of the eukaryotic cell cycle?

G1, S, G2, and M.

Which phases make up interphase?

G1, S, and G2.

What happens during G1 phase?

The cell grows, carries out normal functions, and produces RNA, proteins, and other molecules but does not replicate DNA.

What does G stand for in G1 and G2?

Gap.

What happens during S phase?

DNA replication occurs, duplicating each chromosome.

What does S stand for in S phase?

Synthesis.

What happens during G2 phase?

The cell continues growing and synthesizes proteins and RNA needed for mitosis.

When does interphase end?

At the end of G2 phase.

What is the longest part of the cell cycle?

Interphase.

What is G0 phase?

A resting or quiescent phase in which a cell has left the cycle and stopped dividing.

What happens during M phase?

Mitosis and cytokinesis occur.

What is mitosis?

The division of a eukaryotic cell nucleus into two daughter nuclei.

What is cytokinesis?

The division of the cytoplasm into two daughter cells.

What happens to DNA quantity between G1 and G2?

DNA quantity doubles during S phase.

Does the number of chromosomes double during S phase?

No. Each chromosome is duplicated into two sister chromatids, but chromosome number remains the same.